Abstract

ECG STUDY IN PATIENTS ON HIGH DOSE ANTIPSYCHOTICS

Objectives: There are many antipsychotic medications that have been shown to be associated with the prolongation of the rate-corrected QT (QTc) interval on the electrocardiogram (ECG). Studies have shown that QTc prolongation is associated with increased risk of arrhythmias and sudden cardiac death. This study aims to identify and study the risk profile of patients on high-dose antipsychotic and to examine the prevalence of rate and rhythm abnormalities, in particular, QTc prolongation. We hope that this study could throw a light on current practice patterns and also could potentially guide us towards safe practice in the future. Methods: We recruited 37 adult outpatients who are on high-dose antipsychotic from the 3 outpatient clinics of the Institute of Mental Health in Singapore. Baseline characteristics risk profiling was performed to identify their pre-existing risk, including checks on Calcium, Potassium and Magnesium levels to rule out confounders. 12 lead ECG was done and reviewed manually by our resident physician. Results: It showed that rate abnormality was detected in 8 patients (22%) and QTc interval prolongation was detected in nearly 12 patients (32.4%) but of those only 3 patients had significantly prolonged QT interval needing the primary treating team to review their psychopharmacology regime. Conclusion: QTc Prolongation was positively linked with a number of cardiovascular risk factors.